Abstract

The operation of an electric power system is a complex one due to its nonlinear and computational difficulties. One task of operating a power system economically and securely is optimal scheduling, commonly referred to as the Optimal Power Flow (OPF) problem. It optimizes a certain objective function while satisfying a set of physical and operating constraints. Optimal power flow has become an essential tool in power system planning and operation. In this paper, a gravitational search algorithm is presented to solve OPF problems while satisfying system equality, in-equality constraints. The effect of security limits such as transmission line limits and load bus voltage magnitudes is also analyzed on OPF problem. The developed methodology is tested on the standard IEEE-30 bus test system, supporting numerical and as well as graphical results.

Abstract

This paper presents an approach for measuring and classifying power quality disturbances using discrete wavelet transform and artificial neural network. The various power quality events are considered they are voltage sag, swell, harmonics, sag with harmonics, swell with harmonics and interruption. Due to the power quality disturbances, the signal is distorted. The energy of the distorted signal is first evaluated with the help of the Multi-Resolution Analysis (MRA) technique of Discrete Wavelet Transform (DWT) and the Parseval's theorem. Second, the energy deviation of the distorted signal with respect to pure sinusoidal signal is at different levels calculated. From these energy features and transient duration the artificial neural network classifies and identifies the disturbances.

[12]. Subhamita Roy, and Sudipta Nath, (2012).
“Classification of Power Quality Disturbances using
Features of Signals”. International Journal of Scientific and
Research Publications, Vol.2, No.11.

[13]. Resende, J. W., Chaves, M. L. R., and Penna, C.,
(2001). “Identification of power quality disturbances using
the MATLAB wavelet transform toolbox”. in Proc. of the
2001 International Conference on Power System
Transients.

Abstract

In this paper voltage source converter is interfaced with renewable energy sources such as solar and wind for power quality improvement. The output of a wind energy conversion system is given as one input to the voltage source converter. Perturb and observation based solar panel is projected for changing irradiance to utilize the maximum obtainable power from the solar panel. The output of wind energy conversion system along with output of solar panel is given to voltage source converter wherein the DC is converted to AC with improvement of power quality. A DC link bus connects both the converters of voltage source converters and AC output of converter is given to non-linear load through a grid connected system. Different digital simulation results are acquired to validate features of voltage source converter for multi input renewable energy sources.

Abstract

The Government of India has sanctioned funds for production of 190 GW in this direction and this solution is a way to reduce the pollution levels. This support of the go-green initiative by the united nations as well and is a step forward in creating a better environment for the future generations to live in. The proposed work aimed at designing a wind-solar hybrid system for light load application. The tools like Qblade and solidworks were used to model and analyze the wind turbine system, the material used for the blade and hub was balsa wood and the tower a tripod type. The power output of 100 W at an average wind speed of 4.5 m/s has been targeted. The work also aimed at providing electricity to the rural area in India which amount to 25000 in number where there is no provision for electricity, this solution may provide the electricity needs of such villages.

References

[1]. E. Akcayoz and I. H. Tunce, (2009). “Numerical
investigation of flow control over an airfoil using synthetic jets and its optimization”. International Aerospace
Conference, Turkey.

[2]. Waleed, (2010). “Numerical investigation of leading
edge blowing and optimization of the slot geometry for a
circulation control airfoil”. Notes on Numerical Fluid
Mechanics and Multidisciplinary Design. Vol.112, pp.183
-190.

Abstract

This paper presents detection and location of fault in underground cables by wavelet transform as it is one of the most efficient tools for analyzing non stationary signals and it has been widely used in electrical power systems. Estimation and determination of fault in an underground cable is very important in order to clear the fault quickly and to restore the supply with minimum interruption [3, 8].The high voltage power cable 500MVA, 11kV, 200 km is modeled in MAT LAB simulink platform. Mexican Hat and coif let wavelet transforms is used to extract the signals and the waveforms are shown. The simulation results shows that wavelet method is efficient and powerful to estimate the faults when they occurs in the underground cables.

[3]. Hassan Pourvali. Souraki, (2009). “A New Approach to
Series Fault Location in Underground Distribution System
Using Combined Neural Networks & Wavelet Analysis”.
International Conference on Electric Power and Energy
Conversion Systems (EPECS), American University of
Sharjah.